The security at Kabul's Intercontinental Hotel wasn't nearly enough to stop nine suicide bombers from setting the place ablaze and killing 12 people last month. But the U.S. military thinks it can do better – by spotting treacherous individuals before they get close enough to cause serious harm. Meet the CounterBomber.

The Army just awarded Science, Engineering and Technology Corporation (SET) an up to $48.2 million contract for a machine that could spot bomb-toting individuals from afar. The Virginia-based company, owed by SAIC, has already sent the CounterBomber to over 40 locations in Iraq and Afghanistan.

So just how does this $300,000 device catch would-be human explosions at a distance? Two video cameras automatically detect and track individuals walking anywhere near the system, within the range of a soccer field. Low-level radar beams are aimed at them and then reflected back to a computer, which analyzes the signals in a series of algorithms.

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"We call it our 'secret sauce,'" says Rick Thornton, the director of business development at SAIC. That sauce is apparently so potent it can spot signs of bombs or weapons hidden under someone's clothing.

It does this by comparing the radar return signal (which emits less than a cell phone) to an extensive library of "normal responses." Those responses are modeled after people of all different shapes and sizes (SET got around to adding females in 2009). It then compares the signal to another set of "anomalous responses" – any anomaly, and horns go off. Literally.

When the computer detects a threat, it shows a red symbol and sounds a horn. No threat and the symbol turns green, greeting the operators with a pleasant piano riff. Seem pretty self-explanatory? It's meant to be.

"We built a system so anyone coming out of chow hall can operate it." Thornton says. "As long as you're not color blind, you can do it."

For those worried that those piercing radar eyes might be seeing a little too much, the system doesn't produce any quasi-nude images, à la TSA (privacy is apparently more of a priority for SET). And while Thornton won't reveal any numbers, he claims the accuracy is much higher than the 40% false alarm rates of airport scanners. The system also detects more than just metal – which is good, since the insurgent bomb of choice is mostly fertilizer.

Even so, this is one of the many, many attempts the U.S. military has made to counter the burgeoning use of improvised explosive devices (IEDs), a major cause of soldier casualties in Iraq and Afghanistan. They don't just come strapped onto a suicide bomber's chest, either – these make-shift weapons turn up in vehicles, buried underground, or on the roadside. Detecting a person-borne IED is just a small part of a much wider picture, one the Pentagon has poured billions of dollars into with only mixed results.

A human bomb-detecting radar contraption is a start, but this is one tough problem to solve. Secret sauce just might not cut it.